Search | Engineering

订阅投稿

首页工程期刊工程焦点工程成就工程前沿关于我们 English

资源类型

期刊论文 1642

会议视频 58

会议信息 8

年份

2024 3

2023 202

2022 250

2021 244

2020 137

2019 81

2018 66

2017 85

2016 62

2015 75

2014 63

2013 72

2012 45

2011 39

2010 64

2009 46

2008 35

2007 57

2006 9

2005 5

展开︾

关键词

3D打印 13

增材制造 9

院士大会 9

SARS-CoV-2 7

营养健康 6

工程管理 5

微波散射计 5

碳中和 5

经济 5

COVID-19 4

Cu(In 4

HY-2 4

医学 4

微波辐射计 4

2019 3

2020 3

2型糖尿病 3

GPS 3

Ga)Se₂ 3

展开︾

检索范围：

排序：展示方式：

Study on tribological and electrochemistry properties of metal materials in H2O2 solutions

Chengqing YUAN, Li YU, Jian LI, Xinping YAN

《机械工程前沿（英文）》 2012年第7卷第1期页码 93-98 doi: 10.1007/s11465-012-0313-8

摘要：

Hydrogen peroxide (H₂O₂) is a kind of ideal green propellant. It is crucial to study the wear behavior and failure modes of the metal materials under the strong oxidizing environment of H₂O₂. This study aims to investigate the wear of rubbing pairs of 2Cr13 stainless steel against 1045 metal in H₂O₂ solutions, which has a great effect on wear, the decomposition and damage mechanism of materials. The comparison analysis of the friction coefficients, wear mass loss, worn surface topographies and current densities was conducted under different concentrations of H₂O₂ solutions. There were significant differences in the tribological and electrochemistry properties of the rubbing pairs in different H₂O₂ solutions.

关键词： hydrogen peroxide wear corrosion wear mechanism

HTML PDF 收藏

Rh₂O₃/hexagonal CePO₄ nanocatalysts for N₂O decomposition

Huan Liu, Zhen Ma

《化学科学与工程前沿（英文）》 2017年第11卷第4期页码 586-593 doi: 10.1007/s11705-017-1659-6

摘要： Hexagonal CePO nanorods were prepared by a precipitation method and hexagonal CePO nanowires were prepared by hydrothermal synthesis at 150 °C. Rh(NO ) was then used as a precursor for the impregnation of Rh O onto these CePO materials. The Rh O supported on the CePO nanowires was much more active for the catalytic decomposition of N O than the Rh O supported on CePO nanorods. The stability of both catalysts as a function of time on stream was studied and the influence of the co-feed (CO , O , H O or O /H O) on the N O decomposition was also investigated. The samples were characterized by N adsorption-desorption, inductively coupled plasma optical emission spectroscopy, X-ray diffraction, transmission electron microscopy, X-ray photoelectron microscopy, hydrogen temperature-programmed reduction, oxygen temperature-programmed desorption, and CO temperature-programmed desorption in order to correlate the physicochemical and catalytic properties.

关键词： Rh₂O₃ CePO₄ N₂O decomposition

HTML PDF 收藏

Optimization of the O/HO process with response surface methodology for pretreatment of mother liquor

《环境科学与工程前沿（英文）》 2021年第15卷第4期 doi: 10.1007/s11783-020-1371-5

摘要：

• Real ML-GFW with high salinity and high organics was degraded by O₃/H₂O₂ process.

关键词： High salinity High organic matters Gas field wastewater O₃/H₂O₂ Response surface methodology

HTML PDF 收藏

H₂ 对Pt-Ba-Ce /γ-Al₂O₃ 催化剂NO_x 存储和还原机理的影响研究 Article

王攀, 裔静, 孙川, 罗鹏, 雷利利

《工程（英文）》 2019年第5卷第3期页码 568-575 doi: 10.1016/j.eng.2019.02.005

摘要：

本研究采用浸渍法制备了Pt-Ba-Ce/γ-Al₂O₃催化剂，利用实验评价了H₂ 对NSR（NO_x storage and reduction）催化剂存储和还原机理的影响，并采用综合表征技术研究了Pt-Ba-Ce /γ-Al₂O₃₂O₃ 上，X 射线光电子能谱（XPS）检测到Ce3+ 和Ce4+ 之间的差异，Ce3+ 和Ce4+ 促进了活性氧在催化剂上的迁移。在NO_x 吸附和脱附循环实验中，随着H₂暴露时间（30 s、45 s 和60 s）延长，NO_x 的存储效率和转化率增加适当增加H₂量加速了硝酸盐或亚硝酸盐的分解，有利于NO_x 存储-还原，并促进了下一循环NSR吸附位点的再生。

关键词： Pt–Ba–Ce/γ-Al₂O₃ 催化剂，物理化学性质，NO_x存储和还原，NO_x 排放，H₂ 还原剂

HTML PDF 收藏

固体氧化物电解池共电解H₂O/CO₂研究进展

范慧,宋世栋,韩敏芳

《中国工程科学》 2013年第15卷第2期页码 107-112

摘要：本文介绍了固体氧化物电解池的结构特点及其用于H2O/CO2的共电解制备H2和CO的工作原理，综述了固体氧化物电解池的组成形式，以及单片电解池和电解池堆用于H2O/CO2共电解反应的国内外研究进展，并阐述了提高固体氧化物电解池共电解效率所亟需解决的问题

关键词：固体氧化物电解池 H₂O/CO₂共电解合成气电解效率水电解

HTML PDF 收藏

The stabilization effect of Al₂O₃ on unconventional Pb/SiO₂ catalyst

《化学科学与工程前沿（英文）》 2023年第17卷第10期页码 1423-1429 doi: 10.1007/s11705-023-2315-y

摘要： Similar to Sn, Pb located at the same group (IVA) in the periodic table of elements, can also catalyze propane dehydrogenation to propene, while a fast deactivation can be observed. To enhance the stability, the traditional carrier Al₂O₃ with a small amount, was introduced into Pb/SiO₂ catalyst in this study. It has been proved that Al₂O₃ can inhibit the reduction of PbO, and weaken the agglomeration and loss of Pb species due to its enhanced interaction with Pb species. As a result, 3Al15Pb/SiO₂ catalyst exhibits a much higher stability up to more than 150 h. In addition, a simple schematic diagram of the change of surface species on the catalyst surface after Al₂O₃ addition was also proposed.

关键词： Pb/SiO₂ Al₂O₃ propane dehydrogenation propene stability

HTML PDF 收藏

含稀释剂的Al-Cr₂O₃体系燃烧合成反应热力学分析与反应模型

张衍诚,潘冶,张传

《中国工程科学》 2004年第6卷第6期页码 63-67

摘要：

对含稀释剂Al203和Cr203的Al-Cr203体系燃烧合成反应进行了热力学计算与分析，讨论了起始反应温度T0、稀释剂Al2O3和Cr2O3的含量对绝热反应温度7^的影响，并得出T<

关键词：金属陶瓷燃烧合成 Al-Cr203体系热力学反应模型

HTML PDF 收藏

Al₂O₃-M_xO_y硬面陶瓷涂层的喷焊制备及性能研究

王飚,王宇栋,李慧玲,张自华

《中国工程科学》 2002年第4卷第9期页码 75-80

摘要：

在碳钢母材上，用氧乙炔焰喷焊镍包铝合金粉末制取预涂层，喷焊50% Al₂O₃+50% Ni的复合粉末制取过渡层，用等离子喷焊Al₂O₃ - M_xO_y复合粉末制取最终涂层。

关键词： Al₂O₃-M_xO_y 涂层等离子抗腐蚀抗磨损

HTML PDF 收藏

Phase equilibrium of the ternary system of NH 4 Cl—CaCl 2 —H 2 O at 50°C

Xia LI, Junsheng YUAN, Zhiyong JI, Jianxin CHEN,

《化学科学与工程前沿（英文）》 2010年第4卷第1期页码 75-77 doi: 10.1007/s11705-009-0296-0

摘要： The equilibrium data on the ternary system of NHCl—CaCl—HO at 50°C were investigated using the wet-residue method. The experimental results show that there are three pure phase crystal areas of NHCl, 2NHCl·CaCl·3HO and CaCl·2HO, two mixture phase crystal areas of NHCl and 2NHCl·CaCl·3HO, and 2NHCl·CaCl·3HO and CaCl·2HO in the system. A new hydration double salt (2NHCl·CaCl·3HO) was found in the ternary equilibrium system for the first time.

HTML PDF 收藏

Accurate quantification of 3′-terminal 2′-O-methylated small RNAs by utilizing oxidative deep sequencing

《医学前沿（英文）》 2022年第16卷第2期页码 240-250 doi: 10.1007/s11684-021-0909-7

摘要： The continuing discoveries of novel classes of RNA modifications in various organisms have raised the need for improving sensitive, convenient, and reliable methods for quantifying RNA modifications. In particular, a subset of small RNAs, including microRNAs (miRNAs) and Piwi-interacting RNAs (piRNAs), are modified at their 3′-terminal nucleotides via 2′-O-methylation. However, quantifying the levels of these small RNAs is difficult because 2′-O-methylation at the RNA 3′-terminus inhibits the activity of polyadenylate polymerase and T4 RNA ligase. These two enzymes are indispensable for RNA labeling or ligation in conventional miRNA quantification assays. In this study, we profiled 3′-terminal 2′-O-methyl plant miRNAs in the livers of rice-fed mice by oxidative deep sequencing and detected increasing amounts of plant miRNAs with prolonged oxidation treatment. We further compared the efficiency of stem-loop and poly(A)-tailed RT-qPCR in quantifying plant miRNAs in animal tissues and identified stem-loop RT-qPCR as the only suitable approach. Likewise, stem-loop RT-qPCR was superior to poly(A)-tailed RT-qPCR in quantifying 3′-terminal 2′-O-methyl piRNAs in human seminal plasma. In summary, this study established a standard procedure for quantifying the levels of 3′-terminal 2′-O-methyl miRNAs in plants and piRNAs. Accurate measurement of the 3′-terminal 2′-O-methylation of small RNAs has profound implications for understanding their pathophysiologic roles in biological systems.

关键词： small RNAs 2′-O-methylation sequencing RT-qPCR

HTML PDF 收藏

Effect of TiO 2 loading on the activity of V/TiO 2 -Al 2 O 3 in the catalytic oxidehydrogenation of ethylbenzene

Xiaohong LI, Wenying LI,

《化学科学与工程前沿（英文）》 2010年第4卷第2期页码 142-146 doi: 10.1007/s11705-009-0233-2

摘要： TiO-AlOmixed oxides with different compositions ranging from 40wt-% to 95wt-% of TiO were prepared by sol-gel method and impregnated with different amounts of VO. Supports and catalysts were characterized by X-ray diffraction (XRD), physisorption, temperature preprogrammed reduction (H-TPR), and ammonia temperature programmed desorption (NH-TPD). TiO content in the support had obvious effect on the crystal structure, texture characteristic, acid property, and catalytic activity in dehydrogenation of ethylbenzene (EB) with carbon dioxide. The highest catalytic activity was acquired when the TiO content was 50 wt-%.

关键词： desorption different TiO-AlOmixed physisorption ethylbenzene

HTML PDF 收藏

Al₂O₃ and CeO₂-promoted MgO sorbents for CO₂ capture at moderate

Huimei Yu, Xiaoxing Wang, Zhu Shu, Mamoru Fujii, Chunshan Song

《化学科学与工程前沿（英文）》 2018年第12卷第1期页码 83-93 doi: 10.1007/s11705-017-1691-6

摘要： A series of Al O and CeO modified MgO sorbents was prepared and studied for CO sorption at moderate temperatures. The CO sorption capacity of MgO was enhanced with the addition of either Al O or CeO . Over Al O -MgO sorbents, the best capacity of 24.6 mg-CO /g-sorbent was attained at 100 °C, which was 61% higher than that of MgO (15.3 mg-CO /g-sorbent). The highest capacity of 35.3 mg-CO /g-sorbent was obtained over the CeO -MgO sorbents at the optimal temperature of 200 °C. Combining with the characterization results, we conclude that the promotion effect on CO sorption with the addition of Al O and CeO can be attributed to the increased surface area with reduced MgO crystallite size. Moreover, the addition of CeO increased the basicity of MgO phase, resulting in more increase in the CO capacity than Al O promoter. Both the Al O -MgO and CeO -MgO sorbents exhibited better cyclic stability than MgO over the course of fifteen CO sorption-desorption cycles. Compared to Al O , CeO is more effective for promoting the CO capacity of MgO. To enhance the CO capacity of MgO sorbent, increasing the basicity is more effective than the increase in the surface area.

关键词： CO₂ capture MgO sorbents Al₂O₃ CeO₂ flue gas

HTML PDF 收藏

Investigation of the effects of humic acid and H 2 O 2 on the photocatalytic degradation of atrazine

Chao QIN, Shaogui YANG, Cheng SUN, Jia ZHOU, Manjun ZHAN, Rongjun WANG, Huanxing CAI,

《环境科学与工程前沿（英文）》 2010年第4卷第3期页码 321-328 doi: 10.1007/s11783-010-0238-6

摘要： A solution of atrazine in a TiO suspension, an endocrine disruptor in natural water, was tentatively treated by microwave-assisted photocatalytic technique. The effects of mannitol, oxygen, humic acid, and hydrogen dioxide on the photodegradation rate were explored. The results could be deduced as follows: the photocatalytic degradation of atrazine fits the pseudo-first-order kinetic well with = 0.0328 s, and ·OH was identified as the dominant reactant. Photodegradation of atrazine was hindered in the presence of humic acid, and the retardation effect increased as the concentration of humic acid increased. HO displayed a significant negative influence on atrazine photocatalysis efficiency. Based on intermediates identified with gas chromatography-mass spectrometry (GC-MS) and Liquid chromatography-mass spectrometry (LC-MS/MS) techniques, the main degradation routes of atrazine are proposed.

关键词： atrazine retardation effect photocatalysis TiO2

HTML PDF 收藏

Interfacial charge transfer and photocatalytic activity in a reverse designed BiO/TiO core-shell

《能源前沿（英文）》 2021年第15卷第3期页码 732-743 doi: 10.1007/s11708-021-0772-x

摘要： In this study, the electronic and photocatalytic properties of core-shell heterojunctions photocatalysts with reversible configuration of TiO₂ and Bi₂O₃ layers were studied. The core-shell nanostructure, obtained by efficient control of the sol-gel polymerization and impregnation method of variable precursors of semiconductors, makes it possible to study selectively the role of the interfacial charge transfer in each configuration. The morphological, optical, and chemical composition of the core-shell nanostructures were characterized by high-resolution transmission electron microscopy, UV-visible spectroscopy and X-ray photoelectron spectroscopy. The results show the formation of homogenous TiO₂ anatase and Bi₂O₃ layers with a thickness of around 10 and 8 nm, respectively. The interfacial charge carrier dynamic was tracked using time resolved microwave conductivity and transition photocurrent density. The charge transfer, their density, and lifetime were found to rely on the layout layers in the core-shell nanostructure. In optimal core-shell design, Bi₂O₃ collects holes from TiO₂, leaving electrons free to react and increase by 5 times the photocatalytic efficiency toward H₂ generation. This study provides new insight into the importance of the design and elaboration of optimal heterojunction based on the photocatalyst system to improve the photocatalytic activity.

关键词： photocatalysis core-shell heterojunction H₂ TiO₂ Bi₂O₃

HTML PDF 收藏

Events and reaction mechanisms during the synthesis of an Al

ZAKERI, H. BAHMANPOUR

《化学科学与工程前沿（英文）》 2013年第7卷第2期页码 123-129 doi: 10.1007/s11705-013-1325-6

摘要： An Al O -TiB nanocomposite was successfully synthesized by the high energy ball milling of Al, B O and TiO . The structures of the powdered particles formed at different milling times were evaluated by X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). Thermodynamic calculations showed that the composite formed in two steps via highly exothermic mechanically induced self-sustaining reactions (MSRs). The composite started to form at milling times of 9–10 h but the reaction was not complete. The remaining starting materials were consumed by increasing the milling time to 15 h. The XRD patterns of the annealed powders showed that aluminum borate is one of the intermediate products and that it is consumed at higher temperatures. Heat treatment of the 6-h milled sample at 1100 C led to a complete formation of the composite. Increasing the milling time to 15 h led to a refining of the crystallite sizes. A nanocomposite powder with a mean crystallite size of 35–40 nm was obtained after milling for 15 h.

关键词： ball milling nanocomposite Al₂O₃ TiB₂